/*
 * Copyright 2024 LinQingYing. and contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * The use of this source code is governed by the Apache License 2.0,
 * which allows users to freely use, modify, and distribute the code,
 * provided they adhere to the terms of the license.
 *
 * The software is provided "as-is", and the authors are not responsible for
 * any damages or issues arising from its use.
 *
 */

package com.linqingying.cangjie.ide.codeinsight.quickDoc.cdoc

import com.linqingying.cangjie.descriptors.CallableDescriptor
import com.linqingying.cangjie.descriptors.DeclarationDescriptor
import com.linqingying.cangjie.descriptors.DeclarationDescriptorWithSource
import com.linqingying.cangjie.doc.psi.impl.CDocSection
import com.linqingying.cangjie.doc.psi.impl.CDocTag
import com.linqingying.cangjie.psi.CjDeclaration
import com.linqingying.cangjie.psi.CjElement
import com.linqingying.cangjie.resolve.DescriptorToSourceUtils
import com.linqingying.cangjie.resolve.caches.resolveToDescriptorIfAny
import com.linqingying.cangjie.utils.liftToExpected
import com.intellij.psi.PsiElement

data class CDocContent(
    val contentTag: CDocTag,
    val sections: List<CDocSection>
)

fun DeclarationDescriptor.findCDoc(
    descriptorToPsi: (DeclarationDescriptorWithSource) -> PsiElement? = { DescriptorToSourceUtils.descriptorToDeclaration(it) }
): CDocContent? {
    if (this is DeclarationDescriptorWithSource) {
        val psiDeclaration = descriptorToPsi(this)?.navigationElement
        return (psiDeclaration as? CjElement)?.findCDoc(descriptorToPsi)
    }
    return null
}
private typealias DescriptorToPsi = (DeclarationDescriptorWithSource) -> PsiElement?

fun CjElement.findCDoc(descriptorToPsi: DescriptorToPsi): CDocContent? {
    return findCDocByPsi()
        ?: this.lookupInheritedCDoc(descriptorToPsi)
}
private fun CjElement.lookupInheritedCDoc(descriptorToPsi: DescriptorToPsi): CDocContent? {
    if (this is CjDeclaration) {
        val descriptor = resolveToDescriptorIfAny()

        if (descriptor is CallableDescriptor) {
            for (baseDescriptor in descriptor.overriddenDescriptors) {
                val baseCDoc = baseDescriptor.original.findCDoc(descriptorToPsi)
                if (baseCDoc != null) {
                    return baseCDoc
                }
            }
        }

        val expectedCDoc = descriptor?.liftToExpected().takeIf { it != descriptor }?.findCDoc(descriptorToPsi)

        if (expectedCDoc != null) {
            return expectedCDoc
        }
    }

    return null
}
